Stride Length and Stepping Duration Adjustments Based on Center of Mass Stabilization Control

The biped robot adjusts stepping variables (i.e., stride length and stepping duration) to achieve robust walking under perturbations. A novel method of integrating center of mass (CoM) stabilization control into the optimization of stepping variables was proposed in this article. The method contains offline and online procedures. In the offline procedure, benchmark CoM stabilization controller coefficients and benchmark transition matrices were derived. In the online procedure, the states in subsequent steps were predicted in real time by transition matrix operations, and stepping variables were optimized by model predictive control (MPC). After MPC, the target stepping variables were input to CoM stabilization controllers to generate stable CoM motion. The combination of stepping adjustment and CoM stabilization control was accomplished with the method, and the advantages are presented in the introduction and demonstrations.